not sure how on earth it would work, unless the water cooled system had a ballcock inside to bung the outlet pipe up once the toilet systern had finished pumping water into it,
i think it would be easier just connecting a water mains pipe to the wc rig and having an exit pipe permenently watering your garden or something.....
though i can imagine why that sort of setup isn't out in the shops to buy lol, think the water companies would be perminently shouting out there's water shortages.
personally i'd prefer having a nitrogen cooled rig if i had the money... i just had a thought, is there anything in the world that actually gets colder as more heat surrounds it besides some of the women out there... (only joking.. i know that was sort of sexist, but couldn't resist it)
joking apart now, is there such a material that responds like that in the world?